Effect of long-term organic practices on yield and nutrients uptake by rice (Oryza sativa L) in an acid Inceptisol

An investigation was carried out to the study the impact of long-term organic farming practices on yield and uptake of nutrients by rice in an acid soil of Assam. The seven treatments were evaluated in randomized block design with three replications. The treatments consisted of T1; Absolute control, T2; Biofertilizer consortia @ 3.5 kg ha-1, T3; Compost @ 5.0 t ha-1, T4; Compost @ 5.0 t ha-1+ Biofertilizer consortia @ 3.5 kg ha-1), T5; Enriched compost @ 2.5 t ha-1, T6: Enriched compost @ 5 t ha-1, T7: Azolla @ 0.5 t ha-1 + Biofertilizer consortia @ 3.5 kg ha-1. Result revealed that significantly higher grain and straw yields were recorded as 34.5 and 57.1 q ha-1 with use of enriched compost @ 5.0 t ha-1 treatments. The grain yield of rice was increased by 14.6 and 43.1% over compost @ 5.0 t ha-1 and control, respectively and statistical similar grain yield was obtained with compost @ 5.0 t ha-1+biofertilizer consortia @ 3.5 kg ha-1 treatment. Application of enriched compost @ 5 t ha-1 significantly improve total nitrogen phosphorus and potassium uptake by rice and found similar to compost @ 5.0 tha-1 + biofertilizer consortia @ 3.5 kg ha-1 (except total K uptake) as compared to other treatments. Total uptake of micronutrient (Zn, Fe, Mn and Cu) by rice significantly enhanced with the use of organic farming practices over control. Thus, the dose of compost could be reduced by using enriched compost to obtain higher crop production with its quality.